Description:

Vitamin K antagonists are the standard of care before and after DC cardioversion for atrial fibrillation; however, this poses logistical issues for some patients. The goal of the trial was to evaluate treatment with the novel oral anticoagulant, rivaroxaban, compared with vitamin K antagonists among participants undergoing cardioversion for atrial fibrillation.

Participants in whom adequate anticoagulation could be achieved or transesophageal echocardiography performed were administered study medications for 1-5 days (early cardioversion), followed by DC cardioversion, and then resumed on study medication for 42 days.

The remaining participants received study medications for ≥21 days (delayed cardioversion), followed by DC cardioversion, and then resumed on study medication for 42 days.

Principal Findings:

Overall, 1,504 patients were randomized. The mean age was 65 years, 27% were women, mean CHADS2 score was 1.4, 7.7% had previous stroke/transient ischemic attack (TIA) or systemic embolism, and 20% had diabetes.

In the delayed cardioversion group, the median time to cardioversion was 22 days in the rivaroxaban group vs. 30 days in the vitamin K antagonist group (p < 0.001).

The primary efficacy outcome occurred in 0.51% of the rivaroxaban group vs. 1.02% of the vitamin K antagonist group (95% confidence interval [CI] 0.15-1.73, p = not significant [NS]). In the rivaroxaban group, four events occurred after early cardioversion, while one event occurred after late cardioversion. In the vitamin K antagonist group, three events occurred after early cardioversion, while two events occurred after late cardioversion.

The primary safety outcome occurred in 0.61% of the rivaroxaban group versus 0.80% of the vitamin K antagonist group (95% CI 0.21-2.67, p = NS).

Interpretation:

Among patients with nonvalvular atrial fibrillation, the use of rivaroxaban pericardioversion is feasible. This medication was associated with a similar incidence of the primary efficacy outcome and major bleeding compared with a vitamin K antagonist. Rivaroxaban also shortened the time to cardioversion when a delayed strategy was employed.